Temperature indicator for hair-curling devices



March 25, 1930. A. E. PAussER TEMPERATURE INDICATOR FOR HAIR CURLINGDEVICES Filed Nov. 15, 1926 Patented Mar. 25, 1930 UNITED STATES PATENTOFFICE ARNAUD E. PAUSSER, OE PHILADELPHIA, PENNSYLVANIA Applicationfiled November 13, 1926. Serial No. 148,174.

This invention relates to hair curling apparatus of the type used ingiving permanent waves. This type of apparatus ordinarily includes aplurality of electrically .5 heated chambers in which the individuallocks of hair are confined for the heat treatment by which the wave orcurl is effected.

The heaters of any one set are identical and have a predetermined ratingas regards voltage and current consumption. Also, a statement is givenas to the length of time the current is to be applied in order to bringthe interior of the heater to the proper maximum temperature underspecified operating conditions.

Due to differences in the voltages of the supply lines in differentlocalities, to variations in certain individual lines, and todifferences in atmospheric conditions, there has been no assurance thatthe internal temperatures of the heaters are the required ones, andfrequently the temperatures either exceed the allowable maximum, withdamage to the hair, or fail to reach the maximum, with poor results anda tendency to blame the heaters as inoperative.

It is the principal object of this invention to provide novel means foraccurately gauging the temperatures within the heaters under allconditions.

In the attached drawings, in which I have illustrated an embodiment ofmy invention Figure 1 illustrates a well known type of hair wavingheater to which the device finds ready application, and

Fig. 2 is a longitudinal sectional view illustrating the details of thetemperature indicator.

WVith reference to Figs. 1 and 2 of the drawings, which illustrate apreferred form of heater of the type involved, the heater may comprisean inner tube 1 which is open at one end for reception of a rod 2, thisrod with a lock of hair wrapped around it being inserted in the open endof the tube 1 and held therein by suitable clamping means .4: at thetop. The rod 2 carries at the bottom a suitable closure member 5 whichbears tightly against the normally open end of the tube 1 andeffectively closes the latter. The

inner tube 1 is surrounded by an electric heating coil 6, and this coilis surrounded and protected by an outer casing or shell 7 which issuitably united with the inner tube 1. Conducting wires 8 extend fromthe heating coil 6 through the outer casing 7 and provide means forattaching the heater in an electric circuit. The details of the heaterhave no important bearing upon the present invention, and the abovedescription will be sufficient to afford a complete understanding of thelatter.

In order to provide means for accurately determining the length of timethe current shall be allowed to flow through the coil to give a desiredpredetermined temperature in the interior of the heater, I propose toprovide each set of heaters with a device such as illustrated in Fig. 2.This device preferably comprises a standard heater similar to the othersof the set and including the inner and outer casings l and 7 and thestandard heating coil 6. In this instance, however, the lower open endof the inner tube 1 is closed P by means of a detachable closure elementsuch as a cork stopper 9 or by other desirable means, and atthe top ofthe casing 1 I provide a restricted opening in which may be insertedwith a close fit a temperature indicating element 11, preferably builton the liquid-level thermometer principle. In conjunction with thisindicator, I provide at the top of the heater body a suitable dial plateor disk 12 which preferably will have marks which in conjunction withthe element 11 55 will indicate the temperature in the interior of theheater. A wire guard 10 carried in the present instance by the cork 9prevents the thermometer from contacting with the wall of the casing.

In the normal practice of treating hair with these devices, it iscustomary, by one means or another, to introduce a predetermined amountof moisture into the heater with the hair. This moisture increases thelength of time required to attain a given temperature in the heater. It1s therefore desirable, in order to avoid the necessity of havingmoisture in the heater holding the indicator 11, to calibrate theindicator not in it accordance with actual temperatures in the heaterbut so as to indicate on a dry basis the temperature corresponding tothe desired maximum under actual operating conditions. This may be doneby first noting the time required to bring the heater to the desiredmaximum temperature under actual operating conditions; thereafterapplying current to the indicating heater with no moisture present for acorresponding period of time; and marking on the dial the position ofthe top of the column at the end of this period. Thereafter, regardlessof the voltage applied to the heating coils, the registering of the topof the column with this mark indicates thatthe desired maximum isattainedin allthe heaters. If desired, a second mark or marks may beprovided on the dial indicating the maximum on a wet basis,

or any intermediate temperatures.

The dev ce is of importance in rendering practicable the manufacture andsale of this type'of'heater over extended areas; in insuring properoperation under all conditions; and in preventing possible injury to thehair from excessive heat.

I claim 1. In a hair-curling apparatus, an electrical heating elementwhereby the curled hair is heated, and a temperature indicatorcomprising a secondelectrical heating element electrically connected tothe first mentioned heating element, and a heat-responsive inclicatorassociated with said second heating element to indicate a predeterminedtemperature condition at the curled hair.

2. Ina hair-curling apparatus, a group of electrical heating elementswhereby the curled hair is heated, and means for indicating apredetermined temperature condition at the curled hair, said meansincluding a heat-responsive indicating member, and an electrical heatingelement whereby said member is actuated, the last mentioned heat ingelement being electrically connected to said group of heating elements.

3. In a hair-curling apparatus, an electrical heating element wherebythe curled hair is heated,.means for obtaining apredeterminedtemperature condition at the curled hair, said meansincluding a switch to control the delivery of currentto said heatingelement, a heat-responsive member associated with said switch, andanelectrical heating element whereby said heat-responsive mem her isactuated, the lastmentioned heating element being electrically.connected'to the first mentioned heating element.

ARNAUD E. PAUSSER.

